Roc d'Ardenne: Course, Elevation & Route Profile

Course & Elevation

The start is on the Place de l'Église in the middle of Houffalize, and the course gives you no warm-up: at kilometre 0.1 a 1.35-kilometre climb begins, averaging 8.7 percent and touching over 13. From there the loop runs into the forests and plateaus of the Ardennes between Houffalize and Bastogne.

The marathon is the only distance of the festival that reaches far south into the Bastogne area – demonstrably so from the organizer's own feed zones, since Gives, Wigny and Rue Vieux Château are served by this route alone. Further long climbs follow at kilometre 11.9, at kilometre 28.5 with almost two kilometres and 120 metres of gain, and at kilometre 37.

The profile moves between 301 and 470 metres, so the altitude is modest and the climbing comes from the sheer number of ascents. 6.3 percent of the route is in the steep-uphill band and 6.4 percent in the steep-downhill band, which describes this course well: short hard ramps and equally steep descents on forest tracks and singletrail, with almost no recovery ground between them. It is ridden on a festival weekend with an expo, a DJ set and an après-bike in the centre of Houffalize.

Pacing Strategy

The trap is at kilometre 0.1. An 8.7-percent climb straight out of the start arch, on a cold engine and in a dense field, is the most expensive mistake on this course: follow the wheels there and you will have nothing at kilometre twenty, with seventy kilometres of the same structure still to come.

The course is roughly forty short strength efforts. Ride every one of them well below what you could produce on a single hill, and treat the descents as what they are: recovery, but only if you ride them cleanly. With 6.4 percent of the route in the steep-downhill band on forest ground, poor descending costs more energy here than the climbs do.

The race is decided in the south, between kilometres 28 and 45 – the section only the long distance rides, holding the route's longest climb at kilometre 28.5 and the greatest distance from the finish. Eat and drink deliberately at the Gives and Wigny feed zones, because there is a long gap after them until Engreux, and the last twenty kilometres back to Houffalize are anything but flat.

Training plan for Roc d'Ardenne: 12-week build

For 90 kilometres and around 1,900 metres of climbing on forest tracks and trails, allow four to seven hours in the saddle – average speed on technical ground sits well below a road loop of the same length. The effort is a long aerobic base with roughly forty strength efforts of one to four minutes threaded through it.

What decides it is repeatability rather than any single climbing performance, and on top of that comes the technical factor: over six percent of the route in the steep-downhill band on loose forest ground demands handling that holds up under fatigue. Train only watts and not riding, and you will lose your time going downhill.

So build on two pillars. First, interval blocks of one to four minutes at and above threshold with short, incomplete recoveries – eight to twelve repetitions, ridden on real gradients. Second, long off-road rides of four to five hours with 1,200 to 1,800 metres of climbing whose final third is technically demanding, which is exactly the combination that carries you through the last twenty kilometres.

Early-May conditions in the Ardennes are changeable: ten to eighteen degrees, rain possible at any point, and forest ground that stays wet and greasy for days afterwards. Ride deliberately in the wet, settle tyre choice and pressure beforehand on similar ground, and plan fuelling for long gaps between feed zones – four to seven hours off-road burns more than the raw distance suggests.